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作者：Amiouny, SV; Bartholdi, JJ; Vate, JH
作者单位：University System of Georgia; Georgia Institute of Technology
摘要：We develop heuristics for problem that models the static balancing of turbine fans: load point masses at regularly spaced positions on the periphery of a circle so that the residual unbalance about the center-which corresponds to the axis of rotation of the fan-is as small as possible. We give worst-case guarantees for our heuristics in terms of residual unbalance. For the case of an even number of blades, we show that one of our heuristics provides the same worst-case guarantee (with respect ...
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作者：Barnhart, C; Jin, H; Vance, PH
作者单位：Massachusetts Institute of Technology (MIT); Emory University
摘要：In this study, we formulate the railroad blocking problems as a network design problem with maximum degree and flow constraints on the nodes and propose a heuristic Lagrangian relaxation approach to solve the problem. The new approach decomposes the complicated mixed integer programming problem into two simple subproblems so that the storage requirement and computational effort are greatly reduced. A set of inequalities are added to one subproblem to tighten the lower bounds and facilitate gen...
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作者：Xia, CH; Shanthikumar, JG; Glynn, PW
作者单位：International Business Machines (IBM); IBM USA; University of California System; University of California Berkeley; University of California System; University of California Berkeley; Stanford University
摘要：Consider a flow shop with M machines in series, through which a set of jobs are to be processed. All jobs have the same routing, and they have to be processed in the same order on each of the machines. The objective is to determine such an order of the jobs, often referred to as a permutation schedule, so as to minimize the total completion time of all jobs on the final machine. We show that when the processing times are statistically exchangeable across machines and independent across jobs, t...
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作者：Dawande, MW; Hooker, JN
作者单位：International Business Machines (IBM); IBM USA; Carnegie Mellon University
摘要：A new method of sensitivity analysis for mixed integer/linear programming (MILP) is derived from the idea of inference duality. The inference dual of an optimization problem asks how the optimal value can be deduced from the constraints. In MILP, a deduction based on the resolution method of theorem proving can be obtained from the branch-and-cut tree that solves the primal problem. One can then investigate which perturbations of the problem leave this proof intact. On this basis it is shown t...
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作者：Anily, S; Bramel, J
作者单位：Tel Aviv University; Columbia University
摘要：We consider the problem of servicing a number of objects in a discrete time environment. In each period, we may select an object that will receive a service in the period. Each time an object is serviced, we incur a servicing; cost dependent on the time since the object's last service. Problems of this type appear in many contexts, e.g., multiproduct lot-sizing, machine maintenance, and several problems in telecommunications. We assume that at most one object can be serviced in a given period....
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作者：Cheung, KL; Hausman, WH
作者单位：Hong Kong University of Science & Technology; Stanford University
摘要：This paper studies a continuous review two-echelon inventory system with a supplier serving multiple retailers. Each location uses a decentralized (Q,R) policy based on installation stocks. Each retailer may set a unique reorder quantity as a multiple of a basic packaging size Q. The supplier, in turn, adopts a similar batch replenishment policy. Our objective is to derive the exact steady-state performance for the supplier. We show that the inventory position at the supplier can be easily cha...
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作者：Dawson, CS; McCallum, CJ Jr; Murphy, RB; Wolman, E
作者单位：George Mason University
摘要：This historical account of operations research at Bell Laboratories was drafted in the late 1970s when the authors were part of the Operations Research Center within Bell Laboratories at AT & T; it has not previously appeared in the open literature. We have added a few references to later publications that describe particular aspects of the period covered. Discussions of technological practices and organizational arrangements expressed in the present tense represent a viewpoint of about 1980, ...
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作者：Bashyam, TCA
摘要：We examine two competing technologies for delivering business information to professional subscribers: first, a package service that delivers information using physical media, such as CD-ROMs; second an online service that allows subscribers to access information over online networks. We model the information services market as a duopoly. where each information service provider is equipped with either packaged or online information delivery technology. They compete for potential subscribers ch...
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作者：Chen, FR
作者单位：Columbia University
摘要：In many production/distribution systems, materials Row from one stage to another in fixed lot sizes. For example, a retailer orders a full truckload from a manufacturer to qualify for a quantity discount; a factory has a material handling system that moves full containers of parts from one production stage to the next. In this paper, we derive optimal policies for multi-stage serial and assembly systems where materials flow in fixed batches. The optimal policies have a simple structure, and th...
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作者：Shi, LY; Olafsson, S
作者单位：University of Wisconsin System; University of Wisconsin Madison; Iowa State University
摘要：We propose a new randomized method for solving global optimization problems. This method, the Nested Partitions (NP) method, systematically partitions the feasible region and concentrates the search in regions that are the most promising, The most promising region is selected in each iteration based on information obtained from random sampling of the entire feasible region and local search. The method hence combines global and local search. We first develop the method for discrete problems and...
